[lyfia]

Thanks for the help but actually I've already done that. I've also ruled out recent Windows updates. It seems I'll have to do a full reinstall/reset to fix the drivers, but it's a bit off-topic.

Attached are 3 books that I've read in the past 2 months without problems with the calibre reader. I've even highlighted and taken notes. Only the Japanese book ("kimi no suizou") still works now. Perhaps you can tell the difference between what works and what doesn't.